1
1-22
4
Repeat steps 2 and 3 if necessary. Allow the loader to
operate at this setting until the oil temperature has
increased to 160° F (71ºC), operating temperature.
5
Turn the flow control valve further to restrict the oil
flow to no flow. (Zero) Correct pressure setting is 2400
psi +/- 100 psi (165 bar +/- 6.9 bar).
6
If adjustment is necessary, shut down the auxiliary
hydraulic system, shut off the engine and return the flow
control valve to the open position. Locate the control
valve in the engine compartment.
7
Loosen the jam nut on the relief valve adjusting
screw and turn the screw clockwise, counting the turns,
until the screw bottoms out. (fig. C4233)
8
Turn the screw back. Reduce the number of turns
that you turned in to increase the pressure, increase the
number of turns to decrease the pressure.
9
Retake the pressure readings by performing steps 2
through 5. If necessary make further adjustments by
repeating steps 6 through 9.
NOTE: If adequate pressure and / or flow is not
available, the gear pump could be failing, the intake to
the gear pump is restricted, or the filter in the relief
valve is clogged.
Control Valve Replacement
1
Remove any attachment and shut off the engine.
Turn the key on with the safety devices activated so the
pedals can be moved. Slowly jog both pedals and press
the electric auxiliary switch. This will take any pressure
out of the system.
2
Disconnect the control cables, electrical solenoid
spool locks, and electrical auxiliary solenoid wiring
connectors if equipped. (fig. C4234, C4235)
3
Disconnect the the inlet hose coming from the gear
pump. Cap the hose and fitting and remove the adapter
fitting in the control valve. (fig. C4234)
4
Disconnect the 6 hoses going to the boom, bucket
and auxiliary circuits. Marking the hoses as you remove
them is recommended to ease re-assembly and assure the
circuits are functioning properly at restart.(fig. C4445)
5
Disconnect the accumulator line from the electric
auxiliary circuit and remove the adapter fitting. Plug and
cap all open ports and hose ends.
C4234
C4235
C4445
C4233
Relief valve
Jam nut
CONTROL VALVE 1.3
Clean the work area prior to repair. Cap all open
lines, fittings and ports to prevent contamination.
IMPORTANT
Inlet
Return line
Solenoid coil
mounting nuts
Cable cotter
pins
Solenoid coils
removed
Remove and tag hose location
